President Donald Trump claimed at a meeting with congressional leaders Monday that he lost the popular vote to Hillary Clinton in last November's election because between three million and five million "illegals" cast ballots, multiple sources told Fox News.

It is not the first time Trump has made the unverified claims about illegal immigrants casting votes for Clinton, the Democratic nominee. In late November, Trump tweeted that he had "won the popular vote if you deduct the millions of people who voted illegally." At the time, multiple law enforcement sources told Fox News that there was no evidence for Trump's claims.

The president was joined by Republican and Democratic leaders from the House and Senate for a reception in the State Dining Room.

The Washington Post reported that Trump spent the first 10 minutes of the gathering rehashing the election campaign. During that period, he made his claim about the illegal votes.

House Majority Leader Kevin McCarthy, R-Calif., alluded to it, telling reporters that Trump and the lawmakers talked about "the different Electoral College, popular vote." Asked if anything surprised her about the meeting, House Democratic Leader Nancy Pelosi, D-Calif., said, "I won't even go into that."

Trump defeated Clinton in the Electoral College, collecting 304 votes to her 227. However, Clinton won the popular vote by more than 2.8 million ballots cast.

Others at Monday's reception included Vice President Mike Pence and top Trump aides Reince Priebus and Steve Bannon, as well as Trump's son-in-law and senior adviser Jared Kushner.

Fox News' Chad Pergram and Matt Dean contributed to this report. The Associated Press also contributed to this report.